Packing



May 7, 1929. c. R. HUBBARD PACKING Filed Deg. 10. 1926 INVENTOR ByAttorneys, 41am;

Patented May 7, 1929.

} burrs!) STATES 1,712,003 PATENT OFFICE.

CECIL R. HUBBARD, F NEWARK, NEW YORK, ASSIGNOR TO THE GL'RLOCK PACKINGCOMPANY, OF PALMYRA, NEW YORK, A CORPORATION OF NEW YORK.

PACKING.

Application filed December 10, 1928. Serial no. 163,090.

This invention relates to improvements in packing of the type having arelatively thin lip portion adapted to be forced into snu engagementwith the surface to be packe by the fluid confined in the packedstructure. It is an object of the invention to provide a packing of theabove-described character,

of which the lip will tend to maintain a normal position with itsworking surface in intimate contact with the surface to be packedirrespective of the fluid pressure, which need be relied upon only toincrease the pressure between the surface of the lip and the surface tobe packed.

It is a further object of the invention to provide a packing of, thecharacter described, of which the lip is weakened along the zone of itsconnection with the body portion of the packing, thereby forming aflexi-' 'ble or hinge-like joint between the lip and the body portion,whereby the fluid pressure may more readily maintain the lip in a sealedrelationship with the surface to be packed.

In the drawings illustrating the preferred form of the invention-.-

Figure 1 is a perspective view of a fragmentary strip of packingembodying the invention, a part of which is illustrated in transversecross-section.

Fig. 2 is a similar view of a strip of material from which packing likethat illustrated in Fig. 1 may bemade.

Fig. 3 is a perspective view of a stri of packing like that illustratedin Fig.1, cut

into an annulus or ring, apart of the ring being broken away and a partillustrated in transverse cross-section.

Fig. 4 is an enlarged cross-sectional view of the packing ringillustrated in Fig. 3, the

portion indicated in broken lines being representatiye of the form whichwould be assumed by the lip if not constructed in accordance with one ofthe features of the invention.

Referring first to Fig. 1 of the drawings,

a packing embodying the invention herein sought to be protected isillustrated as comprising a relatively massive body portion 20, 59 ofL-shaped form in cross-section, of which the two arms 21 and 22 in theform herein represented are perpendicular to each other.

Extending from the free end of the arm 22 is a lip portion23 preferablyof wedge-like form in cross-section, said lip having an outer surfaceportion 24 whichis an extension of the outer surface 25 of the end ofthe arm 22 of the L. Preferably the surface 24 W-lll be slightlyinclined or flared outwardly with respect to the surface 25, for reasonswhich wlll be explained. The inner surface 26 of the lip 23 may flareinwardly from the free edge portion 27 of the lip, whereby its thickestor most massive portion s located at a distance from the edge 27 and inthe region of its zone of connection with the end of the arm 22 of theL. .In accordance with one of the important features of this invention,however, the lip is intended to be weakened in any appropriate manneralong this zone of connection between the 11p and the body portion ofthe packing, thereby forming a relatively flexible or hinge-like joint,the importance of which will hereinafter be made clear. One satisfactorymethod of weakening the joint between the lip and the body portion, asillustrated in Fig. 1, consists ingrooving the lip along the zone ofconnection as at 28. Preferably this groove and the angle at thejunction of the arms 21, 22 of the L may comprise a gradually roundedsurface extending from the base of the inner surface 29 of the arm 21 tothe inner surface 26 of the lip portion 27. The form of this groove 5may be such as to deepl undercut the base portion of the lip, therelocalizing a zone of weakness therealong a out which the lip as a wholemay be flexed.

Packing of the above-described character is preferably made inrelatively long strips which may be cut to suitable lengths and bent toring-like form, as indicated in Fig. 3. The size of the rin will bedependent upon the diameter of t e piston or plunger or other part ofthe mechanism to be packed.

When bending the strip of packing from its rectilinear form illustratedin Fig. 1 to the ring-like form'in Fig. 3, the packing at the innercircumference of the mug is sub- 100 jected to compression and thepacking at the outer circumference is put under tension, since the samelength of packing material must be caused to adjust itself to theshorter internal circumferential portion as that 105 which accommodatesthe outer and relatively longer circumferential portion. In view of thiscompression the relatively thin lip portion of the packing would have atendency during the bending of the strip to ring- 110 like form toassume a position of the largest permissible diameter which would onlybe limited by the stresses set up in the material. For example, if thestrip of packing of rectilinear form as indicated in 1g. 1 were to beprovided with a li having its working surfaces 24 and 25- 1n the sameplane instead of having the portlon 24 flared outwardly, the bending ofthe packlng to ring-like form would cause the 11p to be forcedoutwardly, with respect to the center of the ring, to the positionindicated in broken lines in Fig. 4. This would be quite unsatisfactorysince it? would permit the fluid to enter the gap between the surface 24and the surface to be packed and thereby defeat the intended purpose ofthe packing. It is one of the objects of the invention to overcome thisundesirable deformation of the lip when bending the acking fromrectilinear form to circular orm. This is accomplished, as alreadyexplained, by glvmg the packing a normal form illustrated in Fig. 1 inwhich thesurface 24 of the lip portion is inclined away from the arm 21of the L. On bending the packing from rectilinear form to circular form,the compression in the lip portion tends to cause such portion to assumea diameter somewhat greater than it would assume if the lip were toretain its normal cross-sectional form relative to the body portion ofthe packing. This tendency to increase its diameter is overcome by thestresses in the elements of the packing parallel with the axis of thering, the various elements being brought to a state of e uilibrium whenin the form illustrated in ull lines in Fig. 4. The initial inclinationof the packing in rectilinear form may be of such de ree that when bentto ring-like form the sur aces 24 and 25 shall be in substantially thesame plane. The packing is of course placed in the apparatus to bepacked with the channel of V-shaped cross-section lying between thesurfaces 26 and 29 opposed to the fluid to be confined. This fluid willbe caused to enter the V-shaped channel and will have a tendency toforce the lip portion 23 into firm engagement with the surface to bepacked, which it may more readily do if the packing is also providedwith the flexible or hinge-like joint along the zone of weakness betweenthe lip and the body portion.

Packing of the above-described character may be constructed in anyappropriate manner and of any suitable material. In the preferred formherein disclosed it is indicated as having been made by first folding asheet 30 of rubber and asbestos fibre or other ap ropriate fibrousmaterial in a plurality o folds, as indicated in Fig. 2, the last foldbeing carried entirely. around the mass ofimaterial so as to form acovering or envelope for the internal folds. This folded mass ofmaterial may then be pressed in a suitable mold and vulcanized in theform illustrated in Fig. 1. The continuously curved surface at the baseof the V-shaped channel tends to the longevity of the packing since itavoids the use of anysharp reentrant angle which would serve as astarting point or a line of rupture between the base of the lip and thebody portion. When using a packing reinforced with layers of asbestosmaterial the durability of the packing may be further enhanced, asillustrated in Figs. 1 and 2, by so disposing the fibrous material thatthe layers 31 will closely follow the curved surface extending from thesurface 29 around to the surface 26 without an intermediate break orangle.

t is not essential. that the packing be made in the specific form hereindisclosed for pur ses of illustration but should be regard as includingmodifications and variations within the scope of the appended claims.The more important features, as already described, are the body portionand lip portion united by a weakened portion formin a flexible orhinge-like joint between t e two, and the packing having the surfaces 24and 25 disposed in different planes but adapted to be brought tosubstantiall the same plane when the packing is bent rom the form in,which it is made to the form in which it is intended to be used.

What I claim is: 1. A acking comprising a relatively massive bo yportion, a lip portion, and an intervening zone of weakness andrelatively great flexibility forming a hinge-like connection betweensaid lip and body portions, one surface portion of said lip portionbeing an extension of a surface portion of said body portion andcooperating therewith as a working surface of said packin 2. A ackingcomprising a relatively massive b0 y portion and a lip portion onesurface portion of said lip portion ein an extension of a surfaceportion of said body portion and cooperatin therewith as a workinsurface of said pac ing, the other surface 0 said lip portion beingflared from the free edge of said lip to a relatively massive portionadjacent its zone of attachment with the body portion, said lip portionbeing grooved along said zone of attachment to provide a relativelyflexible connection between said lip portion and said body portion.

3. A acking comprising a relatively massive body portion of L-shapedform in crosssection and a tapered lip portion of wedgeshaped form incross-section extending from one arm of the L in the general directionof its other arm, the external surface of said lip portion being acontinuation of the surface of the end of the arm of the L of which thelip is an extension, and its inner surface ,lip portion being acontinuation of the surface of the end of the arm of the L of which thelip is an extension, and its inner surface being flared inwardly fromits free edge to its zone of attachment with the L-shaped body portion,the inner surface of said body portion being continuously curved fromthe base of the free arm of the L to the inner surface of the lipportion, the form of such curved portion being such as to provide aninternally disposed groove along the zone of attachment between the lipand the body portion, thereby producing a relatively flexible hinge-likeconnection between said parts.

5. A packing as defined by claim 2, constructed of ru ber compositionand reinforcing layers of fibrous material, a part of said reinforcingmaterial being so disposed as to closely follow the surface of thegroove along the zone of attachment between the li portion and the bodyportion.

6. X packing comprising a relatively massive body portion and a lipportion, one surface portion of said lip portion being an extension of asurface portion of said body portion and cooperating therewith as aworking surface of. said packing, said packing sion, whereby thedistortion of the lip portion, when the packing is bent to circularform, will tend to cause its working surface to become a continuouscylindrical extension of the cylindrical working surface of the bodyportion, the normal inclination of the lip portion being such that itwill be directed towards the axis about which the packing is intended tobe bent to circular form.

7. A packing comprising a relatively massive body portion of L-shapedform in crosssection and a tapered lip portion of wedgeshaped form incross-section extending from one arm of the L in the general directionof its other arm, the external surface of said lip portion being'acontinuation of the surface of the end of the arm of the L of which thelip is an extension, and its inner surface being flared inwardly fromits free edge to its zone of attachment with the L-shaped body portion,said packing being made in rectiilinear form with the external surfaceof its i portion normally inclined away from .the rec arm of the L,whereby, when the packing is bent to the form of an annulus,

with the lip portion at the part of smallest diameter the distortion ofthe lip ortion will tend become a continuous cylindrical extension ofthe cylindrical surface of the end of the L CECIL R. HUBBARD.

to cause its working sur ace to o

